Your child's lunchbox rating may be written in the stars, says Choice

A ham and cheese sandwich, muesli bar and milk popper might seem the typical combo for a school lunch box. But the differences in the overall nutritional value can be huge, depending on the brands.

Consumer group Choice has applied the algorithm for the healthy food star rating system - controversially removed by Assistant Health Minister Fiona Nash - to children's lunch box staples, giving them the star ratings that could appear on packaged foods from July.

''We found big nutritional differences between similar-looking products, and this is critical when it comes to kids' food,'' said Choice campaign manager Angela Cartwright. ''Eat it every day, and it can add up quickly.''

The analysis showed wholemeal, salt-reduced and skim options tended to get a higher number of stars. There was a big difference in cheeses, with Bega's country light tasty cheese receiving four out of five stars, compared with the basic version's 1.5 stars.

''But we also make products with natural smoke flavours, fat and texture to match, which suit consumers looking for the ultimate eating experience.''

Western Star and Meadow Lea original spreads are low in sugar and high in kilojoules, but the former's ''extremely high'' saturated fat content put its star rating at 0.5.

''I wouldn't call Western Star butter unacceptable,'' Ms Cartwright said. ''But people should make their buying decisions knowing ''saturated fat is implicated in chronic disease and the best dietary advice is to limit consumption''.

The rating system fails to take into account a person's total dietary intake, a Western Star spokeswoman said. ''Butter, when added to vegetables to help your children enjoy foods they wouldn't otherwise eat, is not addressed by this system.''

Lisa Elias, mother of Abbie, 7, and Austin, 10, said she was ''alarmed'' about Western Star's low rating, but she would continue to buy it as her children preferred the taste of butter over margarine.

The Forest Lodge family have a ''healthy but pragmatic'' approach to lunch-packing Ms Elias said, and their lunch boxes often carried dinner leftovers, sandwiches, pizza slices, fruit and cake.

''I'll take notice if there's a substantial difference in stars, but if it's only a one or half a star difference, then it won't impact my decision,'' she said.

Choice used the ''finalised algorithm'' for the star rating calculator - designed with the input of nutritionists, public health experts and the food industry - which was available on the federal website before it was pulled down.

Ms Nash has been censured for misleading the Senate about her then chief of staff and his alleged role in the website's removal.

Veteran nutritionist Rosemary Stanton, who sits on the technical committee for the front-of-pack labelling system, does not doubt the accuracy of Choice's results.

''It shows clearly how important such a system is to improve the overall processed foods available,'' Ms Stanton said.

Her tips for parents include pre-preparing sandwiches with many fillings such as lean meat, hard-boiled eggs or canned fish, and freezing them. They should defrost by lunchtime. Parents should include fruit and snacks such as wholegrain crackers paired with cheese.

Devondale declined to comment, while Tip Top did not return calls. The Australian Food and Grocery Council said it would not comment without the full report.